[0001] The invention relates to a cartridge for on- or offline cleaning installations, such
as incinerators, heat exchangers, flue gas channels, and silos, comprising a casing,
e.g. a sleeve, containing a pyrotechnical mixture, in particular a class P2 pyrotechnical
mixture, and/or components of a pyrotechnical mixture and comprising an electrical
detonator for initiating deflagration of the mixture. Other applications include,
but are not limited to, bundles of heat exchanger pipes, evaporators, economizers,
washers/scrubbers, cyclones, catalysts, absorbers, spray dryers, cooling towers, funnels,
and various filters.
[0002] The invention also relates to a system comprising such a cartridge and a lance for
holding, cooling, and positioning the cartridge inside an installation.
[0003] WO 2011/096872 relates to a rock cracker cartridge (numeral 1 in the figures of
WO 2011/096872) which contains a cracking powder charge (6) and an ignition capsule (30) with an
ignition powder charge (29) in an ignition unit sleeve (31) which does not possess
the mechanical strength that would be required for the ignition powder charge to be
exploded in the open air when ignited. In the rock cracker cartridge there is also
provided an ignition assembly sleeve (7a) which surrounds the ignition unit sleeve
when the rock cracker cartridge is primed. In combination, the assembly which surrounds
the cracking powder charge, and which comprises the ignition unit sleeve and the ignition
assembly sleeve, has a sufficient strength for an adequate pressure to be developed
in the assembly such that the ignition powder charge will explode and generate a flame
of fire and the ignition unit sleeve as well as the ignition assembly sleeve be penetrated
by the pressure and the flame of fire, said flame of fire igniting the cracking powder
charge.
[0004] DE 20 2017 001549 relates to a system for deslagging containers and plants by means of blasting, wherein
a classified as a so-called firecrackers / pyrotechnics, disintegrants (z. B. class
IV, T1 or T2), in the vicinity of the pollution or Caking or slagging is brought,
and the explosive mixture is made to explode.
[0005] Although pyrotechnics are by some perceived as relatively safe when compared to gelatinous
explosives, such as ethylene glycol dinitrate, diethylene glycol dinitrate, nitro-glycerine,
in practice they are not safer.
[0006] It is an object of the present invention to provide an improved cartridge for cleaning
installations by means of pyrotechnics.
[0007] To this end, the cartridge according to the present invention is characterized by
a housing which accommodates the detonator and which housing is attached to the casing
and movable between a first (safe) position, wherein the detonator is isolated from
the pyrotechnical mixture, and a second (primed) position, wherein the detonator extends
in the pyrotechnical mixture.
[0008] In an embodiment, the housing or detonator on the one hand and the casing on the
other hand comprise engaging parts that enable moving, and preferably also locking
after priming, of the detonator to inside the mixture by relative sliding and/or rotation
of the detonator and the casing.
[0009] In a refinement, the housing or detonator on the one hand comprises at least one
protrusion, such as a cam, key, or external screw thread, or a groove, such as an
bayonet slot or an internal screw thread, and the casing on the other hand comprises
a groove or protrusion, respectively, cooperating with the protrusion or groove in
or on the housing to define a path of the relative movement.
[0010] Thus, the cartridge can be primed at the work, e.g. some moments prior to its use,
by establishing e.g. a screw, bayonet, or snap fit connection between the detonator
and the casing.
[0011] In an embodiment, a blocking mechanism, such as a ring that can be torn off e.g.
by breaking it, is located between the housing and the casing, to prevent inadvertent
priming.
[0012] In an embodiment, the donator is at the distal end of the housing and exposed at
least laterally.
[0013] In another embodiment, the mixture is a suspended, e.g. fluidized (upon shaking)
powder, i.e. a powder loose in the casing, a compactable powder, i.e. a coherent mass
which can still be compacted to such an extent that it allows the detonator to be
extended directly into the mixture, or a compacted powder with a defined cavity for
receiving the detonator.
[0014] The invention also relates to a cartridge comprising a casing containing a pyrotechnical
mixture and/or components of a pyrotechnical mixture and comprising an electrical
detonator for initiating deflagration of the mixture, wherein the detonator is configured
to initiate deflagration of the mixture at a current of at least five Ampere, preferably
at least ten Ampere, preferably at least twenty Ampere.
[0015] The Meta-pyro pyrotechnical igniter mentioned in
WO 2011/096872 has a firing current of max 2,12 A, see
http://www.meta-pyro.cz/en/technical-specifications. By providing, in accordance with the present invention a detonator having a firing
current of at least 5 A, the risk of accidental detonation resulting from sparks or
static electricity, occurring e.g. during transport or at a work, is reduced.
[0016] In an embodiment, to shield it from static electricity and/or moist, in the first
position of the housing, the detonator is enclosed or encapsulated by a synthetic
material, such as a thermoplastic polymer.
[0017] In a refinement the casing is made of or laminated with a synthetic material. In
another embodiment, the casing is water- and/or dust tight.
[0018] This will increase safety in that contamination of the work with pyrotechnical mixture
leaking from the cartridge is avoided or at least reduced and in that the risk a dud
cartridge, e.g. a misfire, is reduced.
[0019] In an embodiment, the casing is enveloped by a thermally insulating material and/or
a liquid absorbing material.
[0020] Thus, the cartridge is for, e.g. a few minutes, protected from heat and/or cooled
by a coolant, such as water soaking the liquid absorbing material.
[0021] The invention also relates to a cartridge comprising a casing containing a pyrotechnical
mixture and/or components of a pyrotechnical mixture and comprising an electrical
detonator for initiating deflagration of the mixture, comprising a plurality of compartments
and wherein the compartments contain different components of the pyrotechnical mixture.
[0022] This allows mixing of these components, e.g. by removing or breaking the wall(s)
between the compartments and shaking the cartridge, a short time before its use, thus
further increasing safety, in particular during transport.
[0023] In an embodiment, the nett mass (NEM) of the mixture is in a range from 20 to 1000
grams, preferably in a range from 20 to 500 grams.
[0024] The nett mass of the mixture and the dimensions and shape of the cartridge determine
to some extend the speed of the deflagration and the size and shape of the shock wave.
E.g. a smaller nett mass will typically result in a higher deflagration speed and
a shock wave of relatively small dimensions, providing a fierce and localized blow.
[0025] In another embodiment, the mixture is in accordance with class P2 of directive 2007/23/EC
of the European Parliament and of the Council of 23 May 2007 on the placing on the
market of pyrotechnic articles. The mixture may for example comprise a reducing agent
or fuel, such as black powder, aluminum, boron, titanium and/or magnesium; and an
oxidant such as sodium nitrate, potassium chlorate and/or potassium perchlorate. Preferred
examples of pyrotechnical mixtures include black powder, aluminum and potassium perchlorate.
[0026] In an embodiment, the detonator is a wireless detonator configured to initiated deflagration
upon receiving an encrypted radio signal.
[0027] In another embodiment, the cartridge is coupled to a controller by a set of wires,
which controller is configured to continually measure electrical resistance of the
wires and the detonator.
[0028] Thus, it is possible to continually monitor the condition of the system and reduce
the risk of a misfire.
[0029] The invention also relates to a system for on- or offline cleaning installations,
such as incinerators, heat exchangers, flue gas channels, and silos, comprising a
cartridge according to any one of the preceding claims, a lance, which is provided
at its proximal end, i.e. the end (to be) held by and thus close to an operator, a
supply for a coolant, such as water or a mixture of air and water, and a connector
and/or electrical wires to connect the detonator to a controller and which is provided
at its distal end, i.e. the end far or farthest from the operator, with a head for
holding the cartridge and provided with outlets, e.g. nozzles, or ducts for supplying
coolant to or about the cartridge.
[0030] In an example, the wires of the detonator are connected to the wires in the lance,
the cartridge is primed and the cartridge is fixed in the head of the lance. Next,
the coolant supply is turned on and the cartridge is inserted, by means of the lance,
through an opening, such as a manhole, in an online installation and positioned adjacent
a surface or element, such as a bundle of heat exchanger pipes, to be cleaned. A spray
or mist of coolant surrounds the cartridge to prevent it from untimely deflagration.
When at the desired location, the detonator is activated and the mixture deflagrates,
thus cleaning the adjacent surface or element.
[0031] EP 1 275 925 relates to a process and device for local destruction of compact material, e.g. clinker
coating, masonry remains, etc., in hot thermal systems such as heat exchangers, industrial
ovens, furnaces, and metallurgical melting vessels, which uses an explosive (numeral
5 in the Figures) arranged on the front end of a lance (3) in a cooling container
(1) through which coolant (4) flows.
[0032] EP 1 067 349 relates to a device, system and method permitting online explosives-based cleaning
and deslagging of a fuel burning facility (31) such as a boiler, furnace, incinerator,
or scrubber. A coolant, such as ordinary water, is delivered to the explosives (101)
to prevent them from detonating due to the heat of the online facility. similar device.
[0034] US 5,494,004 relates to an online pulsed detonation/deflagration soot blower.
[0035] The invention will now be explained in more detail with reference to the drawings,
which show a preferred embodiment of the present invention.
Figure 1 is a perspective of a cartridge according to the present invention comprising
a detonator and containing a pyrotechnical mixture.
Figure 2 is partial cross-section of the cartridge shown in Figure 1 with the detonator
in a safe position.
Figure 3 is partial cross-section of the cartridge shown in Figure 1 with the detonator
in the primed position.
Figure 4A and 4B show the housing of the detonator.
Figures 5A and 5B show an insert for rotatably receiving the housing of the detonator.
[0036] Figure 1 shows a cartridge 1 for on- or offline cleaning installations, such as incinerators,
heat exchangers, flue gas channels, and silos. The cartridge comprises a casing, in
this example, a cylindrical sleeve 2 closed at one end and open at the other end,
a detonator 3 that is accommodated in a housing 4, which housing in turn is mounted
in the open end of the sleeve, such that it is movable between a first (safe) position,
shown in cross-section in Figure 2, wherein the detonator is isolated from the pyrotechnical
mixture 5 inside the sleeve, and a second (primed) position, shown in cross-section
in Figure 3, wherein the detonator extends directly in the pyrotechnical mixture.
[0037] The open end of the sleeve 2 is provided with an internal groove 6, in this this
example an internal screw thread that defined in an insert 7, shown in more detail
in Figures 5A and 5B, that is fixed, e.g. clamped, welded, or glued, in the open end
of the sleeve.
[0038] The housing 4 accommodating the detonator 3 has a first section 4A, that has the
same cylindrical shape and the same diameter as the sleeve 2 and from which section
the wires 8 of the detonator 3 extend, and a second section 4B that carries at least
one protrusion, e.g. two projections 9, or an external screw thread.
[0039] The (distal) end of the second section 4B contains the actual detonator 3 and comprises
a plurality of openings 10 and a disc-shaped front wall 11 having a diameter that
is equal to the internal diameter on the insert 7. Thus, when the housing 4 is in
the first (safe) position, the detonator 3 is in a closed chamber defined by the inner
wall of the insert 7 and the front wall 11 of the housing 4 and, when the housing
4 has been moved to the second (primed) position, the detonator 3 is, via the openings,
in direct contact with the pyrotechnical mixture 5 of at least communicates directly
with the cavity in the sleeve 2 containing the mixture 5.
[0040] In this example, the angle between the safe and primed positions of the housing and
the detonator is defined by the pitch, P, of the internal screw thread and the distance,
D, between the (proximal) end of the sleeve and the (distal) end of the first section
4A of the housing 4. If the pitch, P, of the internal thread is twice the distance,
D, the housing must be turned over an angle of 180 degrees to prime that cartridge
and lock, by friction, the housing and the detonator with respect to the sleeve. In
an embodiment, a blocking mechanism, such as a ring (not shown) that can be torn off
e.g. by breaking it, is placed in the space provided by the distance, D, to prevent
inadvertent priming.
[0041] The casing, housing, and insert were made from an thermoplastic material. Suitable
manufacturing methods include injection moulding, extrusion, and 3D printing.
[0042] The cartridge of the present invention can be primed at the work, e.g. some moments
prior to its use, efficiently and by a straightforward act.
[0043] The invention is not restricted to the above-described embodiments, which can be
varied in a number of ways within the scope of the claims.
1. Cartridge (1) for cleaning installations, such as incinerators, heat exchangers, flue
gas channels, and silos, comprising a casing, e.g. a sleeve (2), containing a pyrotechnical
mixture (5) and/or components of a pyrotechnical mixture and comprising an electrical
detonator (3) for initiating deflagration of the mixture, characterized by a housing (4) which accommodates the detonator (3) and which housing (4) is attached
to the casing (3) and movable between a first position, wherein the detonator (3)
is isolated from the pyrotechnical mixture (5), and a second position, wherein the
detonator (3) extends in the pyrotechnical mixture (5).
2. Cartridge (1) according to claim 1, wherein the housing (4) or detonator (3) on the
one hand and the casing (2) on the other hand comprise engaging parts (9; 6) that
enable moving of the detonator (3) to inside the mixture (5) by relative sliding and/or
rotation of the detonator (3) and the casing (2).
3. Cartridge (1) according to claim 1 or 2, wherein the housing (4) or detonator (2)
on the one hand comprises at least one protrusion (9) or a groove and the casing (2)
on the other hand comprises a groove (6) or protrusion, respectively.
4. Cartridge (1) according to any one of the preceding claims, wherein the donator (3)
is located at or near the distal end of the housing (4) and exposed at least laterally.
5. Cartridge (1) according to any one of the preceding claims, wherein the mixture (5)
is a suspended powder, a compactable powder, or a compacted powder with a defined
cavity for receiving the detonator (3).
6. Cartridge (1) according to any one of the preceding claims or the pre-amble of claim
1, wherein the detonator (3) is configured to initiate deflagration at a current of
at least five Ampere, preferably at least ten Ampere, preferably at least twenty Ampere.
7. Cartridge (1) according to any one of the preceding claims, wherein, in the first
position of the housing (4), the detonator (3) is enclosed or encapsulated by a synthetic
material, such as a thermoplastic polymer.
8. Cartridge (1) according to any one of the preceding claims, wherein the casing (2)
and/or the housing (4) is made of or laminated with a synthetic material.
9. Cartridge (1) according to any one of the preceding claims, wherein the casing (2)
is water- and/or dust tight.
10. Cartridge (1) according to any one of the preceding claims, wherein the casing (2)
is enveloped by a thermally insulating material and/or a liquid absorbing material.
11. Cartridge (1) according to any one of the preceding claims or the pre-amble of claim
1, comprising a plurality of compartments and wherein the compartments contain different
components of the pyrotechnical mixture (5) .
12. Cartridge (1) according to any one of the preceding claims, wherein the nett mass
(NEM) of the mixture is in a range from 20 to 1000 grams.
13. Cartridge (1) according to any one of the preceding claims, wherein the mixture (5)
comprises a reducing agent or fuel, such as black powder, aluminum, boron, titanium
and/or magnesium; and an oxidant such as sodium nitrate, potassium chlorate and/or
potassium perchlorate.
14. Cartridge (1) according to any one of the preceding claims, that is coupled to a controller
by a set of wires (8), which controller is configured to continually measure electrical
resistance of the wires (8) and the detonator (3).
15. System for cleaning installations, such as incinerators, heat exchangers, flue gas
channels, and silos, comprising a cartridge (1) according to any one of the preceding
claims, a lance, which is provided at its proximal end with a supply for a coolant
and a connector and/or electrical wires to connect the detonator to a controller and
which is provided at its distal end with a head for holding the cartridge and provided
with outlets or ducts for supplying coolant to or about the cartridge (1).